Biphenylacetylene-based liquid-crystalline materials for the covalent immobilization of antibodies (Ab) onto gold electrodes: The development of novel immunosensors


Dwight A Williams, and Suzanne M. Ruder, Department of Chemistry, Virginia Commonwealth University, 1001 W. Main St, Richmond, VA 23284
The research presented here includes the synthesis of directionally polarized liquid crystalline (LC) materials that are capable of covalently binding Ab onto gold surfaces. The key synthetic steps in synthesizing the LC materials are Sonogashira's cross coupling reaction and a transition metal catalyzed reduction of aromatic nitro groups to N-arylhydroxylamines. Surface immobilized antibodies have recently been used to develop immunosensors capable of detecting low levels of environmental pollutants and biological hazards. Previous studies with surface immobilized antibodies using Electrochemical Impedance Spectroscopy (EIS) have shown consistent changes in surface capacitance due to Ab/Ag complex formation, however, problems with surface regeneration are often encountered. By using LC materials an increase in the sensitivity of the electrochemical measurements should be achieved as well as an improvement in the disruption of the Ab/Ag complex leading to a more efficient surface regeneration.